2008/4/13, Garth N. Wells <[EMAIL PROTECTED]>: > In the down casting functions in GenericTensor, what's the difference > between > > T* t = dynamic_cast<T*>(instance()); > > and > > T* t = dynamic_cast<T*>(this); > ?
// Assume this is configured to use a PETScVector: GenericVector * v = new Vector(); // This won't work: PETScVector * pv = dynamic_cast<PETScVector*>(v); // This will work (and is what down_cast does): PETScVector * pv = dynamic_cast<PETScVector*>(v->instance()); This was the only intended usage for instance(). > Is there much overhead associated with a dynamic cast? > > Garth I have no idea how much overhead there is, but I'm assuming it won't be placed in inner loops anyway. -- Martin _______________________________________________ DOLFIN-dev mailing list [email protected] http://www.fenics.org/mailman/listinfo/dolfin-dev
